1. Field of the Invention
The present invention relates to a method, apparatus, and program of making reservations for execution of programs, and a program execution system.
2. Description of the Related Art
Among computing systems having grid computing technology applied thereto are systems comprising an apparatus of making reservations for execution of jobs, which apparatus can access a so-called resource pool containing a plurality of computers (resources) that execute jobs (programs) of this computation. This apparatus of making reservations for execution of jobs comprises a job reservation information management table, and has a function to assign computers of the resource pool to jobs based on this table. The job reservation information management table contains table data wherein each job is associated with the number of computers required for execution of a job and an execution scheduled time as job reservation information. Such technology is disclosed in, for example, Japanese Patent Application Laid-open Publication No. 2002-318791.
As illustrated in, for example, a time diagram of FIG. 12A, the reservation status of computers (machines 1 to 4) is considered where machines 1 and 2 are reserved for the period of 12:00 to 14:00 for job A and machine 2 is reserved for the period of 16:00 to 18:00 for job B. In this case, the job reservation information management table is configured such that machines 1 and 2 are to be assigned to job A for the period of 12:00 to 14:00 and machine 2 is to be assigned to job B for the period of 16:00 to 18:00.
For this reservation status it is possible to execute, for example, job C that uses two machines for four hours, from 13:00. By making this reservation for job C, the reservation status is updated to a reservation status illustrated in a time diagram of FIG. 12B. Note that it is assumed that all machines 1 to 4 are equal in computation capability.
In the above computing system, reservations for jobs are made by specifically assigning computers to the jobs in the job reservation information management table. For example, in the case where job B is assigned to machine 3 but not machine 1 or 2 as illustrated in a time diagram of FIG. 12C, the problem that reservations for job C cannot be made occurs due to the premise that the same computer is consecutively used. This means that the computers are not being efficiently used.